SYNOPSIS OF THE FAMILY HETEROPYGII. 57 



vi, p. 6 et seq., \vith figs.., Jan., 1872. WYMAN, Mss. notes and drawings in Put- 

 nam, Amer. Nat., vi, p. 16 et seq., 1872. PUTNAM, Amer. Nat., vi. p. 116. Feb., 

 1872 (additional note on the young). 



PLATE 1 (American Naturalist, Vol. vi, Jan., 1872). FIG. 1. Brain, nerves and 

 organ of hearing of Amblyopsis spelceus; enlarged; a, olfactory lobes and nerves; 

 6, cerebral lobes; c, optic lobes; d, cerebellum; e, organ of hearing, showing the 

 semicircular canals, with the otolite represented in place by the dotted lines ; /, 

 medulla oblongata ; g, optic nerves and eye specks. FIG. 2. Otolite, enlarged. 

 FIG. 3. Eye, magnified (natural size one-sixteenth of an inch in length); a, optic 

 nerve; 6, sclerotic membrane; c, layer of colorless cells; d, layer of pigment cells 

 (iris?); e, lens. FIG. 4. Lens, enlarged and showing the cells. FIG. 5. Eye, en- 

 larged, showing the muscular bands, a, a, a, a; b, the lens pressed out of place; c, 

 the optic nerve. FIG. 6. Top of head, showing canals under the skin, natural 

 size. The two black dots and lines indicate the eyes and optic nerves in position. 

 FIG. 7. Top of head, showing the arrangement of the ridges of papillae, nat. size. 

 FIG. 8. One of the ridges of papilla? from the head, magnified. FIG. 9. Three of 

 the papillae from the ridge, still more magnified, showing the cup-shaped summit 

 and projecting filament. Fig. 10. A portion of the ridge magnified, and treated 

 with acid, to show the arrangement of the nervous plexus supplying the papillae 

 with nervous filaments from a branch (a) of the fifth pair. FIG. 11 . Epithelial cells 

 from the head. FIG. 12. Epithelial cells from the body. 



PLATE 2. FIG. 1. Natural size; la, stomach and pyloric appendages, twice nat. 

 size; 16, scale, magnified (nat. size represented by the small outline on the left 

 over the figure); Ic, abdominal cavity, showing position of stomach and single 

 ovary, nat. size. 



Head more than half as wide as it is long. Length of head, from 

 tip of jaw to end of operculum, contained nearly twice in length of 

 body from operculum to base of caudal fin. 



Dorsal and anal fins of equal size, rounded, anal commences under 

 third ray of dorsal. 



Pectorals pointed, reaching to commencement of dorsal. 



Ventrals pointed, nearly reaching to commencement of anal. 



Caudal broad, long and pointed, membrane, enclosing simple rays 

 above and below, continuing slightly on the tail. 



Scales small, longer tljaii broad, with quadrangular centre and from 

 8 to 12 concentric lines, which are broken and reduced in number an- 

 teriorly and crossed by numerous radiating furrows posteriorly.* 



Colorless, or nearly so, with transparent fins. 



Measurements. Largest specimen, 4-5 inches total length. Smallest 

 specimen, 1-9 total length. 



Geographical distribution. Subterranean streams in Kentucky and 

 Indiana. 



Specimens examined : 



PROF. WYMAN'S COLLECTION. 



7 specimens. Half grown and adults. Mammoth Cave. 

 MUSEUM OP COMPARATIVE ZOOLOGY. 



7 specimens. No. 778. Half grown and tf $ adults. Mammoth Cave. 

 1 specimen. No. . Two-thirds grown. Cave near Lost River, Orange Co., Ind. 



*T,The scales described were in every instance taken from the 2d or 3d row un- 

 der the dorsal fin. 



